Grubbs are a branch of the Mudokon family. Not Mudokons as such but it's the closest thing to them. You may think it's a bit daft, but I think it's quite clever. You can go to one part of America and find a species of bear living in that area. Yet you can travel miles and find none of that particular species, yet that area is populated by a different type of bear.
Fuzzles seem to be a world wide creature, like Rats.
Vykker are sophisticated enough to travel from one area of Mudos to the other, so the presence of the Vykker is nothing special. Just like a someone away on bussiness really.
And the rest of your questions belong in the
Forums Suggestions and Help forum.